This research is to be the continuation of a study concerned with the application of proton-induced x-ray emission (PIXE) analysis to biomedical materials. Techniques developed during the past year will be employed to calibrate the system for quantitative analysis of all trace elements, heavier than sodium, which are found in human organs. This technique will be compared to x-ray fluorescence using radioactive sources and possibly an x-ray tube. Emphasis will be placed on trace elements in human organs. Perfusion techniques will be developed and assessed to eliminate artifactual trace element contribution of blood to specific organs. Cell fractionation studies will be employed to determine partitioning of trace elements in cell fractions. Correlations between race element concentrations and biological parameters such as age, sex, disease state, geographic location, and occupation will be investigated. Prime emphasis will be upon cancer, kidney disease, liver disease, and a variety of metabolic diseases. Whole blood and blood serum will be analyzed to study trace level variation in renal failure patients undergoing regular hemodialysis and patients who have had an ileal by-pass for morbid obesity. Research done the first year shows PIXE analysis to have more than adequate sensitivity for these research projects.